Everything You Need to Know About the Pfizer Vaccine

doctor putting vaccine into a syringe

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Key Takeaways

  • Pfizer's version of the COVID-19 vaccine was the first to be approved, making its rounds starting mid-December.
  • Under an Emergency Use Authorization, people over 16 have been approved to get the vaccine.
  • Healthcare workers and residents of long-term care facilities will be the first to get the vaccine.

In mid-December, in the middle of an otherwise bleak month characterized by a precipitous rise in COVID-19 deaths across the country, drug manufacturer Pfizer received emergency authorization to begin distributing their version of a COVID-19 vaccination. 

Here's what you need to know about this COVID-19 immunization option.

All About the Pfizer COVID-19 Vaccine

Approved for people 16 and over, including pregnant and lactating women, the vaccine produced by scientists at Pfizer comes in the form of two injections, given three weeks apart. It will be distributed among all 50 U.S. states. The Advisory Committee on Immunization Practices (ACIP) recommends that the first people to receive the vaccine be healthcare workers and residents of nursing homes or other care facilities.

The COVID-19 vaccine created by Pfizer might be new, but it comes from a wealth of research conducted on other strains of coronaviruses, a class of viruses characterized by spikes that resemble a crown. Other variants of coronaviruses you may be familiar with are SARS and MERS. 

Jason G. Newland, MD, MEd

The Pfizer vaccine was based on studies that were done on previous coronaviruses recognizing that the spike protein is part of the keys to our bodies producing antibodies.

— Jason G. Newland, MD, MEd

According to Jason G. Newland MD, MEd, Professor of Pediatrics at Washington University’s St. Louis Children’s Hospital, “Previous research has allowed us to understand what parts of the virus are important in its life cycle and for our bodies to make antibodies to prevent us from getting sick. The Pfizer vaccine was based on studies that were done on previous coronaviruses recognizing that the spike protein is part of the keys to our bodies producing antibodies.”

Is the Pfizer Vaccine Safe?

For now, Pfizer’s version of the COVID-19 vaccine remains unapproved by the FDA. But that’s more a matter of timing than safety. The pandemic has forced scientists into a race to create a safe and effective vaccine in a mind-bogglingly short amount of time.

Typical vaccine trials can last for years or even decades, but these vaccines—those created by Pfizer, Moderna, and the ones that will certainly follow—have been pushed out on emergency authorizations. That means they're presumed safe for the general public based on limited clinical trials.

The Pfizer vaccine has been well-tested, though, and has been very well-received with few side effects. The FDA's data sheet for the vaccine indicates it’s been tested on roughly 20,000 people in clinical trials and “has been shown to prevent COVID-19 following two doses, given three weeks apart.”

Currently, no data exists on whether the COVID-19 vaccine will be a one-time vaccination or a yearly one like the flu shot. Despite that, “vaccine efficacy is 94% to 95%, which is extremely high,” says Newland.

Side Effects

Side effects have been minimal during clinical trials and include:

  • Pain at the injection site
  • Fatigue
  • Headache
  • Chills
  • Joint pain
  • Muscle pain
  • Fever
  • Injection site swelling or redness
  • Nausea
  • Feeling unwell
  • Swollen lymph nodes (lymphadenopathy) 

Who Should Not Get the Vaccine

You should not get the vaccine if you’ve had an immediate allergic reaction (even if not severe) to any ingredients in an mRNA COVID-19 vaccine or to PEG and polysorbate.

If you have had an immediate allergic reaction to a vaccine or injectable therapy for another disease, talk to your doctor about whether you should receive the vaccine.

The CDC says the vaccine is safe for those with a history of severe allergic reactions, including food, pet, venom, environmental, or latex allergies, however these individuals should be monitored for 30 minutes afterward.  

Can Pregnant Women Get the Pfizer COVID-19 Vaccine?

The uncertainty of the coronavirus pandemic has been difficult for everyone, but perhaps no more so than for pregnant women. If you’re pregnant or breastfeeding and you’re considering the Pfizer vaccine, know that the American College of Gynecology has issued a statement in support of the shot. The official language from the timely statement says, “ACOG recommends that COVID-19 vaccines should not be withheld from pregnant individuals who meet criteria for vaccination based on ACIP-recommended priority groups.”

While the vaccine has been shown safe and effective for the general population, it’s important to note that none of the vaccines currently available under the emergency use authorization have been tested in pregnant women. That means that sadly, there are no safety data to lean on when deciding whether or not to get the COVID-19 vaccine if you’re pregnant or lactating.

Despite that, it has been shown that pregnant women can sometimes have more severe cases of COVID-19 than their nonpregnant counterparts. According to the ACOG statement, “Available data suggest that symptomatic pregnant patients with COVID-19 are at increased risk of more severe illness compared with nonpregnant peers.”

Can Kids Get the Pfizer COVID-19 Vaccine?

For now, Pfizer’s version of the COVID-19 vaccine has only been tested on kids over the age of 16. But Newland expects this to change in relatively short order. “The [vaccine] will eventually be approved for children. [Pfizer and other companies] also are doing clinical trials in children, so the vaccine hopefully will be available for children by the fall.” 

What This Means For You

Though it will take awhile to recognize it, the news on the COVID-19 front is slowly improving. Health teams are working hard to distribute the Pfizer vaccine and its counterparts to those who need it most. In the meantime, it’s important that we continue practicing the health measures that we know can cut down on the spread of the virus: social distancing, mask wearing, and frequent hand washing. 

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